Chiral SU(3) dynamics with coupled channels: inclusion of p-wave multipoles

摘要

We extend our recent non-perturbative chiral SU(3) coupled channel approach to pion- and photon-induced eta- and K-meson production off protons by including all strong and electromagnetic p-wave multipoles, We identify the p-wave amplitudes of the next-to-leading order SU(3) chiral meson-baryon Lagrangian with a coupled channel potential which is iterated to infinite orders in a separable Lippmann-Schwinger equation. Our approach to eta- and R-photoproduction introduces no additional free parameters. By adjusting a few finite range parameters and the unknown parameters in the Lagan,oian, we are able to simultaneously describe a very large amount of low-energy data. These include the total and differential cross sections of the pi-induced reactions pi(-) p --> eta n, K-0 Lambda, K-0 Sigma(0), K+ Sigma(-) and pi(+) p --> K+ Sigma(+) as well as those of photoproduction gamma p --> eta p, K+ Lambda, K+ Sigma(0), K-0 Sigma(+) The polarization observables measured in eta- and K-photoproduction are particularly sensitive to interference terms between the s- and p-wave multipoles. The total cross section data are remarkably well reproduced in all channels. There remain, however, some open questions concerning details of angular distributions and polarization observables. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 29]